The US did not ratify the 1948 genocide convention until 1988. Reading through some of the debates on ratification, one notes that one reason many in the US didn't want to ratify the convention was a fear that Israel could be prosecuted for genocide. Here's Jesse Helms in 1985:

In his recent podcast, @ezraklein calls the right of return "a lie that has been told to people." He continues, "I think the idea that international law tells you it will work that way is a lie international law is telling you." podcasts.musixmatch.com/podcast/the-ez… He then goes on to say, "There’s no right of return for the Jews who were expelled from Iran. There’s no right of return for the people expelled during partition in India and Pakistan. No right of return for the Germans expelled after World War II out of Eastern Europe."